Commutator cone insulator and method of making the same



June 14, 1949. E. M. HAUSHEER 2,473,248

COMMU OR GONE INSULATOR AND METH OF MAKING THE SAME Filed Dec. 1, 1944 Figi M77 I I I I W 1.1' I 4 l l I I I I l I 50.

Inventor; Em M- HausheeT,

His Attorney.

Patented June 14, 1949 COMMUTATOR. CONE INSULATOR AND- METHOD OF MAKING THE SAME Emil M.Hausheen'Schenectady, N. Y., assignor to General Electric Company, a corporation of New- York Application December 1, 1944,. Serial No. 566,135

6 Claims; (Cl. 171-321) My invention relates to commutator cone insulators and to methods of making the same ior providing an improved uniform thickness and density to the part oi the cone insulator through which the major portion of the pressure of the commutator clamping ring is exerted on the commutator bars.

An object of my invention is to provide an improved commutator cone insulator.

Another object of my invention isv to provide a commutator cone insulator ofimproved construction for insuring uniform thickness. and density of the material in that part of the cone which is subjected to the major portion of the clamping pressure, exerted on the commutator bars.

A further object of my invention is to provide an improved method of making a commutator cone insulator.

Further objects and advantages of my invention will become apparent and my invention will be better understood from the following description referring to the accompanying drawing, and the features of novelty which characterize my invention will bepointed out with particularity in the claims annexed to and forming part of this specification.

In the drawing, Fig. 1 is a plan view of the insulating material of which my improved commutator cone insulator is to be made prior to the forming of the cone insulator; Fig. 2, is a sectional elevational view of a pair of dies and the insulating material used in making my improved commutator cone insulators; Fig. 3 is a side elevational view, partly in section, of a commutator provided with an embodiment of my improved cone insulator; and Fig. 4 is a side elevational view of a commutator fully assembled and provided with an embodiment of my improve insulator;

Commutator cone insulators formed of layers of insulating material, such as mica sheets pasted together and suitably milled or sanded to the desired thickness, have been used in the past. In forming these cone insulators, it ha been customary to slot the inturned end and the inner conical section to provide overlapping fingers which are formed under heat and pressure into a frusto-conical shape adapted to be secured between the inner conical surface of a clamping ring and the complementary conical surface on the inner wedge of the commutator bars forming the commutator. In arch-bound commutators, the assembly is such that the segments are held in place by pressure transmitted thereto through which do not completely meet, whichresult in.

parts of higher or lower density than the remainder of the inner conical portion of the insulator. These non-uniformly dense parts of the cone will tend to cause some of the commu tator bars to become loose or buckle as the commutator ages during operation. J

In order to obtain uniform thickness and den-. sity of the pressure supporting portion of the cone insulator, the, superposed layers of insulatin material, according to myimproved construction, are made of an unslotted portion of insulatin material. As, shown in Fig. 1, a plurality of slots I and 2, are, formed in the inner and outer circumferential edges of an arcuate section of insulating material 3 forming inner andv outer fingers 4 and 5, respectively, withan intermediate unslotted central portion 6. The two radial edges 1, are formed with a tapered thickness, and the arcuate section. of insulating material then is arranged about a frusto-coni-' cal die 8, as shown in Fig. 2, with the two ta pered edges 1 in overlapping relationship with an adhesive therebetween, such that the connection formed by the overlapping edges 1 is, substantially the same thickness'and density as that of the original insulating sheet from which the arcuate section has been out. A second frusto-conical die 9 is arranged over the outer surface of the centralunslotted portion 6, and the fingers 4 and 5 of the outer slotted portion of the cone are then, formed into flanges l0 andv H extending in opposite directions to the adjacent part of the central unslotted portion 6, as shown in dotted lines in Fig. 2. The entire cone insulator is then suitably formed under heat and pressure between suitable die elements to provide the desired thickness and density to the insulatin material of the cone insulator and to assure good adhesion between the adjacent parts of the fingers 4 and 5 which form the multislotted end flange portions l0 and II, respectively, of the finished cone. This finished cone sulator can then be arranged over suitable clamping or mounting rings l2 and IS with a ring insulating element l4 extending between the inturned flanges H! of the two cone insulators of a commutator for retaining a plurality of commutator bars I5 in assembled relationship. Any suitable retaining means may be provided for clamping the commutator rings l2 and I3 together. In Fig. 3, a clamping nut I6 is shown threaded over a complementary threaded portion H on the end of the sleeve portion of the clamping ring 12, and the entire commutator is mounted on a shaft I8. This provides an improved commutator cone and method of making the same which results in a substantially uniform density and thickness to the portion of the cone on which the major part of the pressure is exerted for retaining the commutator bars [5 in assembled relationship and provides an arrangement which minimizes distortion of the commutator surface due to irregularities in the thickness or density of the commutator cone insulator.

While I have illustrated and described a particular embodiment of my invention, m0diflcations thereof will occur to those skilled in the art. I desire it to be understood, therefore, that my invention is not to be limited to the particular arrangement disclosed, and I intend in the appended claims to cover all modifications which do not depart from the spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States, is:

1. A commutator cone insulator formed of superposed layers of insulating material having an unslotted central frusto-conical portion, and a multi-slotted end flange portion on each end thereof extending generally in the opposite direction to the adjacent part of said central portion and at an angle thereto, said slotted end flange portions having the characteristics of flanges having been formed into continuous flanges of substantially uniform thickness.

2. A commutator cone insulator formed of superposed layers of insulating material having an unslotted central frusto-conical portion, and an overlapped multi slotted end flange portion on each end thereof extending generally in the opposite direction to the adjacent part of said central portion and at an angle thereto, said slotted end flange portions having the characteristics of flanges having been formed into continuous overlapped flanges of substantially uniform thickness.

3. A commutator cone insulator formed of superposed layers of insulating material having an unslotted central frusto-conical portion of substantiall uniform density and thickness, and a multi-slotted end flange portion on each end thereof extending generally in the opposite direction to the adjacent part of said central portion at an angle thereto, said slotted end flange portions having the characteristics of flanges having been formed into continuous flanges of substantially uniform thickness.

4. A commutator cone insulator formed of superposed layers of mica sheet material having an unslotted central frusto-conical portion of substantially uniform densit and thickness, and a multi-slotted end flange portion on each end thereof extending generally in the opposite direction to the adjacent part of said central portion and at an angle thereto, said slotted end portions having the characteristics of flanges having been formed into continuous flanges of substantially uniform thickness.

5. A method of making a commutator cone insulator which comprises forming an arcuate section of superposed layers of insulating material of substantially uniform thickness with a tapered thickness at the two radial edges thereof, slotting the inner and outer circumferential edges thereof to a predetermined Width and leaving an unslotted central portion, forming the arcuate section into a frusto-conical shape with the adjacent tapered edges in overlapping relationship with adhesive therebetween, and forming the slotted circumferential edges under heat and pressure into flanges extending in opposite directions and at an angle to the adjacent part of the central unslotted portion.

6. A method of making a commutator cone insulator which comprises forming an arcuate section of superposed layers of mica sheet material of substantially uniform density and thickness with a tapered thickness at the two radial edges thereof, slotting the inner and outer circumferential edges thereof to a predetermined width and leaving an unslotted central portion, forming the arcuate section into a frusto-conical shape with the adjacent tapered edges in overlapping relationship With adhesive therebetween, and forming the slotted circumferential edges into flanges extending generally in opposite directions and at an angle to the adjacent part of the central unslotted portion with overlapping of the slotted parts to provide continuous flanges of substantially uniform thickness.

EMIL M. HAUSI-IEER.

tEFERENCES CITED The following referemces are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,589,464 Frederick 1- June 22, 1926 1,796,052 Schermerhorn Mar. 10, 1931 1,860,158 Peterson May 24, 1932 1,872,269 Frederick Aug. 16, 1932 1,881,916 Parker Oct. 11, 1932 1,907,561 Oldenburg May 9, 1933 1,944,508 Gubler Jan. 23, 1934 1,971,219 Howard Aug. 21, 1934 2,152,323 Moore Mar. 28, 1939 2,225,026 Welsh Dec. 17, 1940 2,367,749 Barbieri Jan. 23, 1945 

